In systems in which small quantities of concentrated solution are to be diluted with a large quantity of a diluent, if two pumps of different capacities are employed for the concentrated solution and diluent, then any error in the pump for the diluent may detrimentally affect the outcome. Such a situation can be particularly dangerous when the concentrated fluid being diluted is blood and is being taken continuously from a patient. If the pump for the diluent is not a precision pump having a small degree of error, the result could be that diluted mixture is pumped into the patient.
In addition, if the concentrated solution to be diluted is blood, it coagulates over a relatively short distance, so that it is advantageous if the dilution of the blood can take place near its source.
Accordingly, it is an object of the present invention to provide an improved method and apparatus which overcomes one or more of the aforesaid problems. Specifically, it is within the contemplation of the present invention to provide an improved method and apparatus for diluting a concentrated solution, such as blood, wherein standard pumps may be employed, and their normal range of error will not detrimentally affect the process.
It is a further object of the present invention to provide an improved method and apparatus wherein the dilution of the concentrated solution takes place near the source of the concentrated solution, such as blood, so that the pumps and other equipment may be placed at a relatively large distance from the source of the concentrated solution.